The invention relates to composite elements having ceramic and metallic components, and more particularly to ceramic and metallic components that are interlocked and methods of making and using the same.
Various types of sensors have been used to measure the distance between two objects. For example, a turbine has a number of turbine blades that are disposed adjacent to a shroud. The clearance between one of the turbine blades and the shroud varies depending on various factors, such as but not limited to, temperature, RPM, load, and age of the turbine. It is desirable that a gap or clearance between the turbine blades and the shroud be maintained for safe and efficient operation of the turbine. A sensor may be disposed within the turbine to measure the distance between the turbine blades and the shroud. The measured distance may be used to direct movement of the shroud to maintain the desired displacement between the shroud and the turbine blades.
Such sensors typically employ a combination of metallic and ceramic components. The metallic components are partially disposed within the ceramic component. Typically, the metallic components and the ceramic components are held together by braze joints. However, since such clearance sensors are primarily employed in harsh environments (such as inside the engine), the high operating temperatures and pressures are challenging for the sensor components, and the braze joints. If the braze joint accidentally fails during the operation, there is a risk of the metallic or ceramic component being liberated into the engine, and possibly damaging the engine.
Accordingly, a need exists for providing a sensor that employs ceramic and metallic components, which will not liberate into the engine during operation. It would also be advantageous to provide an economically viable method of making such a sensor component.